Semiconductor chips and devices may include a variety of logic circuits and sub-systems each operating at different voltage levels. A system fabricated in a chip may be designed to communicate with external systems through communication ports where the logic fabricated in the chip may be operating at a different voltage level than the operating voltage level of the external systems coupled to the chip. Typically, an additional pin can be added in a chip to receive a different voltage supply for input/output operations. However, in many cases, adding an additional pin in a chip is not practically feasible.